JPS5934750B2 - Polyvinyl chloride gasket composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyvinyl chloride gasket composition.

Conventionally, polyvinyl chloride or rubber gaskets come into contact with the acrylic paint surface for aluminum sashes or the acrylic resin molded parts that are installed on vehicles, such as fox lamps, position lamps, direction indicator lamps, tail lamps, etc., making them waterproof. It is used for such purposes.

However, conventional gaskets made of polyvinyl chloride or rubber have poor migration resistance to acrylic resin and poor oil resistance, resulting in cracks in the gasket portion and reduced waterproof function, and cannot be said to be excellent.

The present inventors have investigated various polyvinyl chloride gaskets that do not have these drawbacks, and as a result, have discovered a polyvinyl chloride gasket composition that has excellent migration resistance to acrylic resin and excellent oil resistance, and has completed the present invention. It came to this.

That is, the present invention uses 100 parts by weight of polyvinyl chloride (hereinafter simply referred to as "parts"), a sebacic acid-based polyester plasticizer and/or azelaic acid-based polyester plasticizer with a molecular weight of 7,000 to 10,000, and a trimellitic acid trialkyl ester plasticizer. It is an object of the present invention to provide a polyvinyl chloride gasket composition comprising 40 to 100 parts of a plasticizer, which may contain 40 to 100 parts of a plasticizer, and optionally stabilizers, fillers, pigments, dyes, ultraviolet absorbers, and flame retardants.

Polyvinyl chloride in the present invention is usually a homopolymer of vinyl chloride, but monomers copolymerizable with vinyl chloride,
For example, it is a copolymer of vinyl chloride and a small amount of vinyl acetate, (meth)acrylic acid ester, itaconic acid, etc., or a mixture of a homopolymer and the copolymer.

Furthermore, the plasticizer used in the present invention has an average molecular weight of 7000.
~10,000, azelaic acid polyester and trimellitic acid trialkyl ester with an average molecular weight of 7,000 to 10,000, and sebacic acid polyesters include saturated polyesters of sebacic acid and polyhydric alcohols, and polyhydric alcohols are Propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, etc. alone or in combination;
Azelaic acid polyesters include saturated polyesters of azelaic acid and polyhydric alcohols similar to the above-mentioned sebacic acid polyesters, and trimellitic acid trialkyl esters include tris 2-ethylhexyl trimellitate and tris C7 to Cll mixed alkyl esters. Examples include trisalkyl trimellitate, which is an aliphatic monohydric alcohol alone or a mixed alcohol, such as trimellitate.

In the present invention, this plasticizer is a sebacic acid-based polyexutyl plasticizer, an azelaic acid-based polyester plasticizer, singly or as a mixture, and further mixed with trimellitic acid trialkyl ester, and polyvinyl chloride 100
40 to 100 parts, preferably 50 to 90 parts.

Also, trimellitic acid trialkyl ester is usually used in an amount not exceeding 33% by weight of the total plasticizer, preferably not more than 20% by weight. It should be noted that if the amount of trimellitic acid trialkyl ester exceeds 33% by weight of the total plasticizer, the oil resistance will be significantly lowered, which is not preferable. The sebacic acid polyester and azelaic acid polyester used have an average molecular weight of 7,000 to 10,000. If the average molecular weight is less than 7,000, the non-migration property decreases and it is not useful as a plasticizer for gasket compositions. Moreover, when the average molecular weight exceeds 10,000, the resulting composition becomes hard;
Moreover, the rubber elasticity also decreases, which is not preferable. The composition of the present invention may further contain stabilizers, ultraviolet absorbers, flame retardants, lubricants, fillers, pigments, and dyes as required. The following commonly used system stabilizers are used: barium-dinonylphenol, barium dilaurate, barium diricinolate, barium di-2-ethylhexoate, barium diacetate, barium disolbate, barium disalicylate, barium・J (
octyl malate), barium dibenzoate, calcium distearate, calcium dimyristate, calcium dilaurate, calcium dioctoate, calcium dioctyl phenate, calcium dibenzoate, calcium disalicylate, calcium laurate octoate, calcium di(paratertiary butyl benzoate), strontium distearate, strontium dilaurate, strontium ditoluate, strontium dioctoate, strontium di-12-hydroxystearate, strontium laurate myristate,
Strontium dibenzoate, magnesium distearate, magnesium dilaurate, magnesium dimyristate, magnesium dioctoate,
Magnesium dioctyl phenate, dimethyltin dioctyl maleate, dibutyltin dibutyl maleate, dioctyltin octyl maleate laurate, monobutyltin tributyl maleate, dimethyltin dilaurate, dibutyltin dilaurate, dioctyltin dimyristate, dibutyltin dioctylthioglycolate, Examples include dioctyltin dibutylmercaptopropionate and monobutyltin trioctylthioglycolate, but in addition to the above, commonly used barium soap, calcium soap, magnesium soap, strontium soap, and organic tin compounds are also included. Furthermore, depending on the purpose, there is no problem in using other metal soaps such as cadmium soap, zinc soap, lead soap, bismuth soap, and nickel soap.

The polyvinyl chloride gasket composition thus obtained has excellent migration resistance to acrylic paints or acrylic resin molded products, and also has excellent oil resistance.

The present invention will be explained in more detail by giving Examples and Comparative Examples below.

Example 1 Each of the above raw materials was heated and kneaded with a roll at 165°C to form composition A.
Example 2 The above raw materials were heated and kneaded with a roll at 165°C to obtain a composition (g).

Example 3 The above raw materials were heated and kneaded with a roll at 165°C to obtain a composition.

Comparative Example 1 The above raw materials were heated and kneaded with a roll at 165°C, and composition F was obtained.
j/DD was obtained.

Comparative Example 2 The above raw materials were heated and kneaded with a roll at 165°C to obtain Composition D.

Comparative Example 3 The above raw materials were heated and kneaded with a roll at 165°C to obtain Composition D.

Comparative Example 4 The above raw materials were heated and kneaded with a roll at 165°C to obtain Composition 9.

Test Examples Using the compositions obtained in the Examples and Comparative Examples described above, the following non-migration tests and gasoline resistance tests were conducted.

The results are shown in the table below. (1) Non-migration test on acrylic painted surface Acrylic melamine baking paint is applied on an aluminum plate, and after baking, the resulting painted surface is coated with a thickness of 1m7.
n, each of the above compositions with an area of 40 cd at 0.5 kg/Crl
The condition and surface hardness of the painted surface after being compressed at a pressure of i and a temperature of 70° C. and kept for 72 hours were examined. (2) Non-migration test for acrylic molded products Each of the above compositions was placed on a plate of methyl methacrylate polymer with a thickness of 1m71L and an area of 40cr1i at a pressure of 0.5kg/Cd.
After pressing at a temperature of 70°C and keeping it for 72 hours, the condition of the plate contact surface was examined.

(3) Gasoline resistance test Each of the above compositions was measured in 1 mm x 4 CrIL x 10? After conditioning the film at 23°C for 24 hours, it was immersed in gasoline at 23°C for 5 days.

Claims (1)

[Claims] 1 100 parts by weight of polyvinyl chloride, molecular weight 7000-1
0,000 sebacic acid-based polyester plasticizer and/or azelaic acid-based polyester plasticizer, and may further include a trimellitic acid trialkyl ester plasticizer 40~
A polyvinyl chloride gasket composition comprising 100 parts by weight of stabilizers, fillers, pigments, dyes, ultraviolet absorbers, and flame retardants as required.